Finland has a good system for this. You can take no-longer-wanted household items to your nearest kierrätyskeskus ("recycling center"). They sort thru it, toss the unsellable, check over checkoverable things (think: stereos and sweaters and jigsaw puzzles) to verify they're OK (and affix a label), and put'em on a shelf with a price tag.

These centers are a wonderful source of super-affordable second-hand stuff. The environmental benefits are yuuuge.